Telephone system



Patented Dec. 13, 1932 srrss.

PATENT, orrice ALOIS CAPEK AND FEANS VAN DEN BROECKE, OF A NTWERP, BELGEUM, ASSIGIEORS TO WESTERN ELECTRIC GGMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORA- l:

'TION F NEW YORK TELEPHONE SYSTEM V Application filed S ptember 6, 1924, Serial No. 736,213, and in Great Britain October 8, 1923.

cut-off relay 12, line 2, through the sub- 9 This invention relates to improvements in telephone exchange systems and more particularly to systems employing automatically operated meters at the central oflice for counting and registering completed calls.

An object of the invention is to prevent the metering apparatus from registering in case of a call to an information operator or other station for which no charge should be made.

Another object of the invention is to prevent the automatic operation of the meter should the calling subscriber be entitled to an uncounted connection as for example, in case of a second connection for the purpose of rectifying the calling of a wrong number.

Still another object is to inform the operator of the non-operation of the subscribers meter in the case of a normal connectio which should be counted.

A feature of the invention therefore resides in the provision of a circuit arrangement whereby when the calling plug of the operators cord circuit is inserted in a jack having a sleeve circuit resistance of a certain low value means will be actuated to disable the metering circuit whereby the call may be completed without its being registered on the meter.

Another feature resides in a circuit arrangement whereby the actuation of a key by the operator when the calling plug is inserted in the jack of a called line, and before the called subscriber responds disables the automatic registering means thus preventing the meter from operating.

Another feature of the invention is the provision of signal means and a circuit arrangement therefor for informing the operator should automatic operation ofthe'subscribers meter not take place in case the call should be counted.

Other features and objects of'the invention will be described hereinafter and the invention will be better understood when taken in conjunction with the drawing which shows the embodiment of the invention.

When the calling subscriber, by taking the receiver down initiates a call, current flows from grounded battery 10, through the winding of line relay 13, contact 9, armature 8 of scribers station, back through line 1, to armature of cut-off relay 12 through contact 6 to ground 7. Theline relay 13 becoming and, the line lamp 16 becomes lighted by cur.- rent, flowing from grounded battery. 10,

through armature 14, contact 15, lamp 16, to I ground at 18.

The first operator prepared to answer the call, plugs into the jack J, whereby current flows from grounded battery, through windmg 32 of 550 ohms and winding 33 of 20 ohmsof relay 31, through the sleeve contact 32'. of the plug P, sleeve 24, winding of cutoff relay 12, and to ground 7.- The energization of cut-off relay 12 breaks, the circuit of the line relay l3 and lamp circuit at confacts 6 and 9. Relay 31 operatesbecause the high resistance winding 32 of 550 ohms and the lowresistance winding 33 of 20 ohms are m circuitand in series with the cut-off relay The attraction of armatures 34 and 35 of relay 31 results in the completion of the energizing circuit of supervisory relay 36, v

operators set over armatures 45 and 46 to the calling line, and the operator then ascertains the desired number. After the usual busy test the plug P is inserted in jack 1200 of the required line, completing the circuit for relay' 4:7which extends from ground,

through the winding of the cut-off relay of the called subscriber, indicated by a resistance 201- through the sleeve contacts of jack 200 and plug P, and through both the wind ings of relay 17 to battery. Relay 47 is con-- structed similar to relay 31.

The attraction of armature 18 of relay 47 energized armature 14 engages contact 15, 1- i completes an energizing circuit for relay 44. The attraction of armature 43 of relay 44 breaks the circuit of relay 41, whereby the operators set is disconnected.

If a second or third operator had attempted to answer the call after the first operator had placed plug P in jack J, the relays corresponding to relays 31 and 47 in such second and third cord circuits would be unabled to operate as they would be shunted by the combined resistance of the first cord circuit apparatus in the sleeve wire which is in series with the subscribers cut-off relay, which resistance would be about 42 ohms.

If an operator plugs in on a busy line, relay 49 operates from battery supplied over the tip of the first cord connection, to the line, which circuit can be traced as follows: Battery, left winding of relay 36 associated wiih the first cord connected to the line, alternate contact of armature 34, tip contacts of plug P and jack J, substation apparatus, ring contact of jack J'and plug P of all succeeding cords attempting to make contact with the line, back contact of armature 35 and wind ing relay 49 to ground. Relay 49 in operating closes by means of its left armature 50 a circuit for lamp 51, whereby said lamp is flashed in accordance with the operation of interrupter 52. This gives the operator a visible signal to show that she has plugged into a busy line.

When relay 44 operated it closed an energizing circuit for relay 91, which is as follows, grounded battery, armature 43 of relay 44, conductors 100 and 101, winding of relay 91, armature 102 of relay 88, armature of relay 8910 ground at key 42. The energization of relay 91 closes the circuit through relay 89 for the ringing source 103 (interrupted alternating current).

,VVhen the called subscriber takes down his receiver, relay 89 operates at once, and by attracting its armature opens the shunt (ground) around the relay 88 this shunt consisting of armature 102 of relay 88, back contact of relay 89 and a break contact of key to ground. The relay 88 operates now over a circuit from ground to a break contact of key 111, right winding of relay 88, over Winding of relay 91, leads 101 and 100, over a make contact of relay 44 and its armature 43 to battery. Relay 88 remains locked over its own armature 102 and leads 100 and 101, and over the armature 43 of relay 44 to battery. Relay 91 cannot operate again to put ring-- ing current on the line as long as plug P is plugged in due to its being short circuited by armature 102 of relay 88. Condenser 104 of 0.01 mi. is provided in order that ringing tone may be sent to the calling subscriber to inform him that his party is being rung. The circuit extends through the calling sub scribers loop and back to ground at the relay 36. 0

The ringing is under the control of the: calling subscriber, who, if he desires to abandon the call at this stage, hangs up his receiver, whereby the ringing is discontinued. When the receiver hung up, relay 30 becomes de-energized and closes the following circuit :-grounded battery, arn'iature 43 of relay 44, conductors 100 and 105, key 42, conductors 106 and 107, armature of relay 3b, and thence in parallel through lamp 132 to ground and the 250 ohniwinding of relay S0 to ground. Relay becoming energized at tracts its armature 108 which closes the following circuit z-grounded battery, armature 43 of relay 44, conductors 100 and 105, key 42, conductor 109, armature 108, 120 ohm winding of relay 80, conductor 11.0, 220 ohm winding of relay 88, key 111 to ground. Relay 88, becoming energized, attracts its armature 102 and thus breaks the ringing circuit by short circuiting relay 91.

If the operator desires to speak to the calling party durin the ringing period, she may do so without being interfered with by the ringing tone, the operation of her listening key 42 removes the ground from the energizing circuit of relay 01, thus breaking the ringing circuit.

The operator is unable to listen in. to the conversation as long as both the calling and called subscribers have their receivers oil the hooks, because although she may operate her key 42, to remove the shunt from the right hand winding of relay 41, the circuit for this winding is open at the arinatures of relays 36 and 90.

It will be seen that the supervisory lamp 116 will receive some current during the ringing period, but will not receive Stu, cicnt current to cause it to glow brightly as resistances 113 and 114 are included in its circuit during that time. Thus the operator knows that she need only to take action when the lamp glows brightly a cleaning out signal.

A description of the metering features of the invention will now be given.

When thecalled subscriber takes his receivcr oil the hook, relay 90 is energized, the circuit extending from grounded battery. through the right hand winding of relay 00 (75 ohms) lower armature of relay 01, armature 112 of relay 47, through the subscribers loop and back through the top armatures of relays 47 and 91, left hand windii'ig oi? relay 90 75 ohms) to ground. The energization of relay 90 causes the momentary oper ion of relay 39 over the following c rcuit ground. relay 87, armature 1.15 of relay 0O 0U. conductor 116, lamp 110, armature'oi' relay 00, conductor 117, winding 0t relay 39, (485 ohms) armature 118 of relay 86, winding oi? relay to grounded battery. Relay 81- then becomes energized over th following circuit: grounded battery, 500 ohm winding of relay 84,1eft hand winding 01" relay 80,

Cil

( ohms), armature of relay 39, conductor 119, armature 37 of relay 31, 20 ohm wind.- ing 33 of relay 31 sleeve contact 32, sleeve 24, winding of relay 12 to ground 7. Operating magnet 83 then becomes energized over a circuit extending from ground, armature of relay 8%, winding of magnet 83 to grounded battery. This magnet 83 causes the opera.- tion of the peg count register 120. As soon as contact 121 is closed, current is increased through the 1 100 ohm winding of operating magnet 122, and the operation of this magnet causes the message register 123 to register. As soon as contact 124 is closed, the liOOohm winding is shunted by the ohm winding further increasing the current in conductor 119, so that relay 86 will pull up by means of its left hand winding (35 ohms) and lock it over its right hand winding (600 ohms).

The attraction of armature 118 of relay 86 cuts oif relay 39 from the common registering mechanism.

Thus, sure operation of the meters is ef' fected as they are not cut off until they have registered. Although the potential on the sleeve is thus momentarily increased, such increase is not sufiicient to operate a relay corresponding to relay 31 in a second cord circuit if the answering plug of such second cord circuit had been inserted during the metering operation.

If the calling subscriber desires the information operator, or other station for which there should be no charge the line jacks of which have a low resistance circuit to ground the insertion of the calling plug in the non-charge line J completes an energizing circuit for relay 86. through its middle winding of 12 ohms due to the low resistance of the line sleeve circuit. The attraction of armature 118 of relay 86 breaks the circuit through relay 39 required to operate the meter. Upon operation, relay 86 becomes locked over the following circuit:-ground, armature l8 of relay 17, conductor 125, conductor 126, right hand winding of relay 86, armature 127 of relay 86, conductors 128, 100, armature 13 of relay 4:4, to grounded battery. Relay 85 individual to the cord circuit and relay87 common to a number of cord circuits become energized to cause the display of signals 129 and 151 re spectively. These signals will remain displayed until the. meters have properly functioned. The meter will not register, therefore, in case of a re-ring or if the subscriber moves his receiver hook by mistake, and of course not i f the subscriber has not answered at all.

If, however, the calling subscriber is given a wrong number the meter will operate. The system is, therefore, arranged so thatthe op erator may thereafter connect the calling party to his desired party without making a second registration on the meter. When the operator has been informed that the wrong number has been obtained, she operates the re-ring key 111for a moment after plugging up the right line. This shunts the cut-off relay of the called line with the resistance 113, so that relay 86 operates before the circuit for relay 39 is completed.

Means is'also provided so that if one of the subscribers registers does not operate, or if the 49 ohm winding of meter magnet 122 is open, the attention of the'operator will be called to this fact. If relay 86 does not become energized after relay 90 has operated, relay 85 is energized over the following circuit :grounded battery, winding of relay 85,

armaturellS of relay 86, winding of relay 39, conductor 117, armature of relay 90, lamp 116, conductor 116, armature 115 of relay 88 to ground.

The operation of the common relay causes the lighting of lamp 129, thus attractscriber moves his hook a circuit is completed for relay 80 through its right hand winding which is 250. ohms andis as follows z-ground,

right hand winding of relay 80, armature of.

relay 36, conductors 107 and 106, key 42,0011- ductor 105, armature 43" of relay 44,1 to grounded battery. Lamp 132 lights in parallel withrelay 80. Armature 130 is attracted. and as soon asthe switch hook is released again and relay 36 is energized,the following circuit ;isclosed :grounded battery, interrupter 131, armature 130 of relay 80, armature of relay 36,1amp-132. Onaccount of the action of the interrupter, lamp 132 will flash at regular intervals. This action of course, is dependent upon the position of key 42 and the flashing will stop if the operator operates this key. During the flashing operation, the relay 8O remains locked over its locking cir-' cuit, which is as follows :-ground, at key 111, 220 ohms winding of relay 88, conductor 110, 120ohm winding of relay 80, armature 108, conductor 109, key 42, conductor 105, armature 43 of relay 44 to grounded battery;

In casethe called party hangs up his receiver before the calling party has finished and the latter wishes to continue the conversation, the operators attention is called by actuating the receiver hook in the usual manner, and the operator then operates key 111 which releasesthe relay 88 and the ringing commences again.

The operator may now converse with the callingsubscriber even though neither party has hung up.

The reason why this is possible will now be described. When the relay operated, armature 133 was attracted thus closing the following circuit for relay 82, ground, armature 133 of relay 80, winding of relay 82 to grounded battery. The operation of relay S2 and the operation of key 42, completes an energizing circuit for relay 41 which is as follows :grounded battery, armature 134 of: relay 82, conductor 135, key 42, 250 ohm winding of relay 41, armature 40 of relay 31 to ground. The operation of relay 41 connects the operators set to the line. A locking circuit for relay 82 is provided by the operation of key 42 which is as follows :-grounded battery, armature 136 of relay 82, conductor 137, key 42 to ground.

It is unnecessary for the operator to operate the key 111 when the calling subscriber flashes and wants another connection, as when the calling plug is removed from the jack, relays 44 and 47 release, thus resulting in an unlocking of relay 88.

What is claimed is: r

1. In a telephone system, a calling line, a plurality of called lines one of which has a sleeve circuit resistance substantially lower than the others, a link circuit for interconnecting said calling line with any one of said called lines, said link circuit including a supervisory relay associated with the calling end thereof, a position meter associated with said link circuit, means automatically respon sive to the operation of said supervisory relay when said calling line is connected with one of said high resistance called lines for operating said position meter, and marginal means responsive to the connection of said calling line with said lower resistance called line to prevent the operation of said first mentioned means.

2. In a telephone exchange system, an operators position, a calling subscribers line and :1 called subscribers line terminating at said position, means at said position interconnecting said lines, a service meter associated with said calling line, means including a marginal relay for controlling the automatic operation of said meter when said called subscriber answers, and operator controlled means for operating said marginal relay to prevent the operation of said meter.

3. In a telephone exchange system, an operators position, a calling subscribers'line, and a called subscribers line terminating at said position, a link circuit at said position interconnecting said lines, a service meter associated with said calling line, means for automatically operating said meter when the called subscriber answers, a signal adapted to be displayed when said means is operated, and means including a marginal relay adapted to be operated when said meter is operated to retire said signal.

4. In a telephone exchange system, an operators position, a calling subscribers line anda called subscribers line terminating in said position, means at said position for interconnecting said lines, a call meter at said position, means for automatically operating said meter to register a completed call between said calling and called subscribers, means including a marginal device for controlling the automatic operation of said meter when said called subscriber answers, and operator controlled means for operating said marginal device to prevent the operation of said meter.

In Witness whereof, we hereunto subscribe our names this 14 day of August A. D., 1924.

ALOIS CAPEK.

F. VAN DEN BROEGKE. 

